Treatment of raw materials containing fatty materials



IIREATMENT or RAWMA rams coNIAnsmG iF TT MATERIAL -Israel Harris. Chayen, LondonpEngland, 'assignor toBritv No Drawing. A lication-Febr ar 13, 195-3,

' --Serial-No.336',-887

:14 Claims. (01.260412) This invention relates to the treatment of raw materials containingfatty materials and; more particularly, ;to a process in whi'ch 'pieces of said raw-material ,are subjected to intense impacts while surrounded by or suspendedfin 'a liquid in *which all .or at least part of'the residue of the-raw-material atterseparation of the fatty material "is ;"In-'m y-' eopending application Serial "No. 123 7,3 27ffil6d July 1 8, 195 1, new "Patent-Nun1ber"$635,104, dated llpril 1 4; 1953; "I have disclosed a process for recovering fatdrom materials; containing the same in which pieces o suc'h-imaterials are-subjected*to intense impacts such as a" highspeed sefies of; impactsfrorn 'the hammers of a hammer-mill whilesuch pieces of material are surrounded "byor suspended fin-an-amount of water which is several times Fthe weight ofthe materialbeing treated such that Fthe impacts are "wholly' er -partly delivered -through the Water. "When-treating many types :offat-containing materialfifor examplefbonesyor soft-fat products from most la'nd animals, .t'heirripact treatmentflin the presence of *waterprodu'ces a'rnixture from 'which a material highfin f2t"0lli11t 'flll "be "separated by dilference in specific gravity frommost o'f the" water and'ifrem a residual ma- "teriahmos't 'ofwhich is insoluble in org'does not remain suspended infthewater so as'to"leavevery"little fat in the 'water or residual material and 'also' not more than "-asmllpmportion of-the residual material in solution or suspension in the water. The ,pro cess.di sclosed"in..said 'coperiding-application' is-also;applicable .to raw materials *dther than-bonesarid tsojft fat products from land ani- 'mal s,-" for 'exampl'effish and -fish',livers;as .well as, vegetable flaw smate'ri'alscontainingfatty materials. With: certain '-fish-'=materials,- e.g.,"-h errings, and certain vegetable materials,- =-e. g., olives," so me difficulty is egrperienced "with eeparationyand in ihesecasesatwo stage centrifugal sepairaition is desirably employed as disclosed in my copenjding' application serial' No. "336,888, 'filedTFebruary 13, 195 3.

lZhere are, however,"*certain raw materials containing afatty -material which when subjected to; intense-irnpacts in thepresence of water in accordance with the ,disclosuresof theabove+mentionedapplications produce mixtures whibh present certain "economic --and procedural problems-with respecttothe recovery of substantially-all not the=valuable materials. For example; some raw materialsproduce mixtures in which awsubstantial amount of -desirable components 'of theresidual material," i.e.,--=the portions of the raw material other than thef fatty material, "is 'sel'ublein or remains-suspended in the-watersuchpthat the soluble or suspended material is not easilyseparated from the water and recovered. Also-some raw-materials pro'duce mixtures 1 in i which thefatty material is present in th form=of an oilrin-water emulsion, usually stabilized by -residual material in solution or=- suspension in 'the water; such thatithe fatty :material cannot -be recovered in high yields evenwby stwo istage centrifugal separation; and rimsflmeieases theasame: irawmaterialsiproduce mixtures presenting both types:ofrseparation problems.

theh a r ma eria a dia .d recovered 19m ur m n eds nut meats ,to sm l h r q Ihe wq ii i c n id r d. own Q1 a i eas .sofien ith fieell w lls "ice " q eous so ut ns s t which v watetsqlnblqnrein re les so uble .tha li Wat it qss b 4 11cu e the. los of .su'ch.., xote asr v r s sse ziq herecove n anima ifa si mmrbsznesii r 3L tata odue q ro esse d g vtherecas y of at "T e rn tur ip v th wli uidlempl yed wi lade end .una ea e and th .fa tywma i' e g ee re esi. in en ra rheligui i i na in wh ch a o a leas partpfi -th .r,.i rmat ia fl s sub ant al iri o rubleaandu-cne i which ffil .l. Y-P- arable emulsions having the fat as adisperse phase 'dojiot p sist- .I anygeve ttthe. "Quid s. a, a f tt ma e ia .aadlhe,iresidiia pmatenal are eadilyrsep- 'in p'iece p the rawmat seiimpa t ll flvQ l ldQ fby 9 u pendes n s hrhqui ina arnqunt e a time the gli meof.' heiniece bein r eated "The p oces 9 th p g ent nven t parat qula lyae vantageQuslf r. ra overit 9i I iag. vseed s soyab an cottoasee i. n auuts, na mnkeme nuts and ther s e p am 'filmilarlqlhws: s eci ica ly men i ned- Prio p ocesse ,fq ur r er n oi t am such eed p s 'have'inc'luded'such preliminary steps as, delinlling, P4115" ingw q kia "flak n etc,betoreian a emp i lnad to pa the iqi pfr tqmtheimra WithasQm -g ceq r ntal? o th ses p ra e ,i oyabeans arerno u y dehulled; ilu ear yal qi 1 ,18 eed p wnur rar suh- 'i c t i ii e s i se'a l minar steps-n me y gr n l a ,we in rand fla s ng, .he o esepar ti n of Qil from th meek whe he the s pa at on b lbymec anisalpressng, 1l}y I,' l li,l2IQSSi1lg q e p,

v 1 bycsolven ex a t pn- "-iGri d ngis:emi Q ,dmr r c t edw .siz It, .i herhhot-i wat r. steam emp oyed. cqol agi anrewhsub vthin flakes Such, fla i g is som mes om t d whe 9 separ io oi byrme han ea pressing'bu i a mos unily mp y dpri 1a so ven r istn t on- Eve with xp s vep ei aratiq refc edto b ve, a. Considerable portion of the oil. is ljeftinthe me al in solvent extractign processes evenrafter repeated treatments withthe solvent,

appa ently. because such o u sst r sen i unb oken of the, prior-art, although in someg instances itmaybel advantageous to en' ployrsueb a'zdehull g;:step twhereathis ,stepz is weasilya carried: Qtlllq:WlthOl1t substantialxloss: of oilcontainingzmaterial in i order -.tol=reduce-: .the r amlount of is'olidz residual material inrthe oilsrecoveryuprocess. iwRe- Eduction ofitheramount-ofrvsuch:solid residual materiahwill usually reduce the amount of oil lost by entrainment therein.

In the present process the oil is directly released from the oil cells by the intense impact treatment in the presence of a liquid. In the case where the oil is insoluble in the liquid'employed, the oil can be separated from the liquid and solid residue by differences in specific gravity, and in the case where the oil is soluble in the liquid the re sulting solution may be separated from the solid residue by difference in specific gravity, or by filtration in some cases. Where a liquid is employed in which the oil is soluble, the present process becomes a much simpler and more effective solvent extraction process.

The present process is not limited to the recovery of true fats, i. e., liquid or solid tri-glycerides of fatty acids, but is applicable to the recovery of substantially any fat-like material from raw materials containing the same. That is to say, the recovery of such fat-like materials as animal or vegetable waxes including carnauba or oandalula wax, or sterols or compounds thereof, such as sterol glycosides or sterol esters, which have the same general physical and solubility properties as true fats, from raw materials containing the same in cells or similar structures, is contemplated by the present invention, the term fatty material being employed in the present specification and claims as inclusive of true fats and such fatlike materials as just discussed.

It is therefore an object of the present invention to provide an improved process for recovering fatty materials from raw materials containing the same in which pieces of such raw material are subjected to intense impacts'while surrounded by or suspended in a liquid in an amount which is several times the weight of the material being treated and in which at least some of the solid residue of the raw material after removal of the fatty material is less soluble than in water and in which a resultant readily separable mixture is produced and separated to recover a material high in fatty material content and a residual material low in fatty material content.

Other objects and advantages of the invention will appear in the following more detailed description.

In carrying out a preferred embodiment of the invention, pieces of a raw material containing fatty material in cells or cell-like structures are fed into the inlet of a hammer mill of the type in which a plurality of hammers are carried on the periphery of a rapidly rotating rotor. The rotor is enclosed in a casing having a lower portion closed by a grid provided with openings, preferably in the form of slots, of a size preventing passage of the pieces of raw material therethrough until the pieces have been broken into smaller pieces in the mill. The pieces of raw material may be individual fat-containing seeds or portions thereof or may be whole or broken or cut pieces of the meats of larger seeds or pieces of other raw materials containing fatty materials such as the leaves or other parts of certain plants containing vegetable wax in cells or cell-like structures. The pieces of raw material when fed to the mill are directed into the path of the hammers and, in general, are subjected to intense impacts while freely suspended in or surrounded by a liquid which is simultaneously fed into the mill. That is to say, the pieces of raw material are not crushed or pounded between the hammers and surfaces of the casing but are subjected to repeated intense impacts resulting from collisions between relatively stationary pieces of the raw material and the hammers and collisions between the pieces, after high velocities have been imparted thereto by the hammers, and the walls of the casing, which impacts may be wholly or partly delivered to the pieces through the liquid employed.

The peripheral speed of the hammer is, in general, between 2,500 and 30,000 feet per minute. The resulting intense impacts to which the pieces of raw material are thereby subjected andthe: high relative velocity which is produced between the pieces of raw material and the liquid apparently rupture the fatty material-containing cells of 4 the raw material to release the fatty material and cause it to be scrubbed from the residue of the pieces.

As stated above, water alone is a satisfactory liquid for a large number of raw materials, but in the case of many raw materials a very substantial portion of the desirable components of the residual material is soluble in water or at least is colloidally soluble or remains suspended therein in finely divided form. In such cases, either a large amount of valuable organic material is lost in the water and a major waste disposal problem is presented, or expensive apparatus and additional procedures must be employed to recover such organic material from the water. Also, if water alone is employed as the liquid, a difiiculty resolvable emulsion is sometimes present in the mixture discharge from the mill, which emulsion is in some cases stabilized by residual non-fatty material in solution or colloidal solution or suspended in finely divided form in the water.

By employing liquids other than water, including water containing a modifying solute, the difficulties above discussed can be successfully overcome. The exact nature of the liquid employed will vary with the raw material being treated but, in general the liquid should be inert to the raw material, i. e., it should not have any deleterious chemical reactions with any of the constitu-tents of the raw material and should not be a solvent for any substantial part of the residue of the raw material after removal of the fatty material. The liquid may or may not be a solvent for the fatty material being recovered and should remain in liquid form, i.e., should not solidify or boil at the particular temperature employed in the mill, which temperature will ordinarily be within the range of usual atmospheric temperatures, i. e., from 32 to F. The liquid should have a viscosity of the same order of that of water at the temperature at which it is employed, i.e., it should have a viscosity within the range of approximately A that of water to 4 times that of water on a centipoise scale and should preferably have a viscosity within the range of /2 that of water to 2 times that of water. The liquid should be readily separable from the residual material by such steps as decantation, centrifugal separation or filtration, and with the exception noted hereinafter from the fatty material being recovered by such steps or by evaporation in case the liquid is a solvent for the fatty material.

Examples of liquids which may be employed with various raw materials are liquid hydrocarbons such as hexane or other petroleum fractions, halogenated or other substituted liquid hydrocarbons such as trichloroethylene, or carbon tetrachloride, liquid alcohols such as lower monohydric aliphatic alcohols or liquid glycols including liquid polyalkylene glycols, liquid acetals, esters, ethers, furans, ketones, etc., and even water or other solutions of substantially neutral salts such as alkali metal chlorides or sulfates or alkaline earth chlorides as well as water or other solutions of other organic or inorganic materials including weak acids, tannins, alcohols, ethers, dioxan, etc. Such solutions should be such that all or at least part of the residue of the particular fatty material being treated is substantially less soluble therein than in water, and in the case of certain solutes, for example, aqueous solutions of some of the inorganic salts, the solutions may be saturated. Such solutions may also contain a wetting agent to assist in scrubbing the fatty material from the residual material. In some cases the liquid may be the fatty material being recovered if such fatty material is liquid and has a viscosity in the usable range at a usable temperature in the mill. That is to say, liquid fatty material such as cottonseed oil may be separated from the residual material by such steps as decantation, centrifugal separation or filtration and returned in relatively large quantities to the mill so that a recirculation is set up with part of the liquid fatty material being continuously withdrawn from the process and another part being continuously returned to the mill.

width of ,6 yielded a meal having a residual oil con-tent of about 0.7%. Treatment of the peanuts in hexane, utilizing a grid slot width of resulted in a meal having a residual oil content of about 2%. Treatment of peanuts with methyl ether yielded a meal having a residual oil content of about 1.3

Castor seed with carbon tetrachloride as the liquid and ,5 grid slot yielded a meal having a residual oil content of about 0.6%

With linseed and tric'hloroethylene employing :grid slot widths of 6 the residual oil content of the meal was about 4.9%.

It may he mentioned that in all runs with the various materials trichloroethylene yielded an oil which was darker colored than that recovered when employing carbon tetrachloride or simple hydrocarbon solvents.

I claim:

1. The process of recovering fatty material from fattymaterial-containing raw material, a substantial portion of the residue of which after removal of the fatty material therefrom is at least colloidally soluble in water so as to produce a diificultly separable mixture when pieces of said raw material are subjected to intense impacts in the presence of water, said process comprising, subjecting pieces of said raw material to said intense impacts while surrounded by an organic solvent inent to said material in an amount several times the amount of said raw material and in which at least some of said raw material is substantially less soluble than in water so as to produce a resulting mixture in which fatty material is removed from said pieces to leave residues of said pieces which are readily separable from said resulting mixture, and separating said residues of said pieces from said resulting mixture to leave said solvent containing the removed fatty material.

2. The process of recovering fatty material from fattynraterial-contain-ing raw material, a substantial portion of the residue of which after removal of the fatty material therefrom is at least colloidally soluble in water so as to produce a diflicultly separable mixture when pieces of said raw material are subjected to intense impacts intthe presence of water, said process comprising, subjecting pieces of said raw material to said intense impacts while surrounded by an organic solvent inert to said material in an amount several times the amount of said raw material and in which :at least some of said raw material is substantially less soluble than in water so as to produce a resulting mixture in which fatty material is removedfrom said pieces to leave residues of said pieces which are readily separablefrom said resulting mixture, sepanating'said residues of said pieces from said resulting mixture to leave said solvent containing the removed fatty material and recovering said removed fatty material from said solvent.

3. The process as defined in claim 2 in which the fatty material is soluble in the organic solvent and said residues of said pieces are substantially insoluble therein.

4. The process as defined in claim 3, in which the organic solvent is a hydrocarbon.

,5. The process as defined in claim 3, in which the organic solvent is hexane.

6. The process as defined in claim '3, in which the organic solvent is a halogenated hydrocarbon.

'7. The process as defined in claim 3, in which the organic solvent is carbon tetrachloride.

8. The process of recovering fatty material from fatty-material-containing raw material, said process comprising, subjecting pieces of said raw material to intense impacts in a hammer mill while said pieces are surrounded by an organic solvent in an amount which is several times the volume of saidpieces and in which solvent said fatty material is soluble'and the residues of said pieces substantially insoluble so as toproduce a mixture in which the fatty material is substantially all removed fr m. d

residues and is in solution in said solvent and said residues are in suspension in the solution of said fatty material in said solvent, separating the residues from said solution and recovering'the fatty material from said solution.

9. The process as defined in claim 8, in which the solvent is volatile and the fatty material is recovered from said solution by evaporation of said liquid.

10. The process as defined in claim 9, in which the raw material is a vegetable seed, the fatty material being recovered is a tri-glyceride oil and the solvent is a hydrocarbon.

11. The process as defined in claim 10, in which the raw material is a vegetable seed, the fatty material being recovered is a tri-glyceride oil and the solvent is carbon tetrachloride.

12. The process of treating fatty-material-containing raw material, a substantial portion of the residue of which after removal of the fatty material therefrom is at least colloidally soluble in water when pieces of said raw material are subjected to intense impacts in the presence of water, said process comprising, subjecting pieces of said raw material to said intense impacts while surrounded by an organic solvent inert to said material in an amount several times the amount of said raw material and in which at least some of said raw material is substantially less soluble than in water so as to produce a resulting mixture in which fatty material is removed from said pieces to leave residues of said pieces which are readily separable from said resulting mixture, and separating said residues of said pieces from said resulting mixture to leave said solvent containing the removed fatty material.

13; The process of treating fatty-material-containing raw material, a substantial portion of the residue of which 'after removal of the fatty material therefrom is at least colloidally soluble in water when pieces of said raw material are subjected to intense impacts in the presence of water, said process comprising, subjecting pieces of said raw material to said intense impacts While surrounded by an organic solvent inert to said material in an amount several times the amount of said raw material and in which at least some of said raw material is substantially less soluble than in water so as to produce a resulting mixture in which fatty material is removed from said pieces to leave residues of said pieces which are readily separable from said resulting mixture, separating said residues of said pieces from said resulting mixture to leave said solvent containing the removed fatty material and separating said removed fattymaterial from said solvent. 7

14. The process of recovering liquid fatty material from fatty material-containing raw material, a substantial portion of the residue of which after removal of the fatty material therefrom is at least colloidally soluble in water so as to produce a difficultly separable mixture when pieces of said raw material are subjected to intense impacts in the presence of water, said process comprising subjecting pieces of said raw material to said intense impacts while surrounded by a liquid which is the same as the liquid fatty material in an amount several times the amount of said raw material so as to produce a resulting mixture in which fatty material is removed from said pieces to leave residues of said pieces which are readily separable from said resulting, mixture, and separating said residues of said pieces from said resulting mixture to leave said liquid fatty material containing the removed liquid fatty material.

References Cited in the file of this patent UNITED STATES PATENTS 

1. THE PROCESS OF RECOVERING FATTY MATERIAL FROM FATTYMATERIAL-CONTAINING RAW MATERIAL, A SUBSTANTIAL PORTION OF THE RESIDUE OF WHICH AFTER REMOVAL OF THE FATTY MATERIAL THEREFROM IS AT LEAST COLLOIDALLY SOLUBLE IN WATER SO AS TO PRODUCE A DIFFICULTY SEPARABLE MIXTURE WHEN PIECES OF SAID RAW MATERIAL ARE SUBJECTED TO INTENSE IMPACTS IN THE PRESENCE OF WATER, SAID PROCESS COMPRISING, SUBJECTING PIECES OF SAID RAW MATERIAL TO SAID INTENSE IMPACTS WHILE SURROUNDED BY AN ORGANIC SOLVENT INERT TO SAID MATERIAL IN AN AMOUNT SEVERAL TIMES THE AMOUNT OF SAID RAW MATERIAL AND IN WHICH AT LEAST SOME OF SAID RAW MATERIAL IS SUBSTANTIALLY LESS SOLUBLE THAN IN WATER SO AS TO PRODUCE A RESULTING MIXTURE IN WHICH FATTY MATERIAL IS REMOVED FROM SAID PIECES TO LEAVE RESIDUES OF SAID PIECES WHICH ARE READILY SEPARABLE FROM SAID RESULTING MIXTURE, AND SEPARATING SAID RESIDUES OF SAID PIECES FROM SAID RESULTING MIXTURE TO LEAVE SAID SOLVENT CONTAINING THE REMOVED FATTY MATERIAL. 